Brake mechanism



Nov. 1, 1932. H Q BQWEN E1- AL 1,885,174

BRAKE MEcHA-NISM Filed Feb. 14, 1930' 2 Sheets-Sheet 1 Nov. 1, 1932. H. c. BowEN ET AL BRAKE MECHANISM Filled Feb. 14. 1930 2 Sheets-Sheet 2 ,m/JM. f myf- Patented Nev. 1, 1932 UNITED STATES-PATENT oFFic-E -EEEBEET c. BOWEN Nn JOSEPH a. nEm'noEF, or DETROIT, mcrcan, AssrGNons 'ro 'HYDRAULIC BnaxE courantes Los ANGELES, eALrFonNra, a conroaa'rron or CALIFORNIA BRAKE xEcHANI'sar- 'D application mea rebmary 14, 1930. semi nauseas.

This invention relates to a brake'mechanism and more particularly to such -a device including a devlce for adjusting the distance between two adjacent portions of the friction meansfor compensating for wear of the brake lining. An object of our invention is the provision of a brake' mechanism including friction means vhavin `ends disposed adjacent each other and inc udin improved means whereby said ends naye relativelyadjusted to compensate for wear of the brake lining andl in which the adjusting may be quickly Aand accurately accomplished without removing the brake drum from its normal positlon.

Another object is the rovision of an in-v expensive adjusting mec anism which willI not shift from adjusted .position when subjected to continued and severe vibrations.

In the accompanying drawin illustratin one embodiment of our inventlon,

igure 1 is a vertical section taken on the plane of the line 1--1 o'f Figure 2 passing through Aa brake drum and looking in the direction of the vbrake band and its sup rting pan, the direction of rotation ofthe difiim in the forward movement of the vehicle being indicated by the arrow; Figure 2 is a section 4 Fi re 1;

Aigure 3 is a vertical section similar to Figure 1 and showing a modified form. of brake mechanism incorporating m invention, the direction of rotation of t e drum in the forward movement ofthe vehicle being indicated by the arrow;

Figure 4 1s a planvie'w of a concentric disk hereinafter described; Figure 5 is a plan view of an eccentric hereinafter described; v

Figure 6 isan elevation of a bolt or pivot pin used in my invention.

This invention is articularly useful in conjunction with bra es of the type illustrated in Figures 1 and 2, but is adaptable to many other types of brakes as will readily ap ear. Y

n Fig. 1 a brake band 2 extends ad'acent the inner periphery of a brake drum 1. or cooperation therewith and has its ends held in taken online 2-2 of' lace by pins or bolts 3 and 4. The brake and periphery is provided with a brake lining 5 of usual construction. During operation of the brake the ins 3 and 4 are fixed in osition by means` o nuts 7 and 8 and suitab e means may be employed. forforcibl'y pressing the side of the brake band opposite the pivots into engagement with the drum.

For purposes of illustration we have shown. a mechanism consistin of a hydraulic cylinder 8 and an arm 9 a apted to be actuated by pressure from within the' cylinder. The arm 9 is pivoted to the pan 10 by means of a bolt 11. A downwardly extending ortion 12 ofV arm 9. has a bolt 13 theret rou h which is adapted to engage the bottom o a slot 14 on a thrust arm 15 which in turn is secured by a bolt 16 to a wide reinforcin flange 17 on the brake band 2. For the purpose of retracting the Ibrake band from engagement with the drum upon release of hydraulic pressure in the cylinder 8 w'e have provided a coil spring 21 havingone end 22 engaging a lug 23-xed to the pan by suitable rivets or bolts 24. The upperv en'd 25l of the spring 21 engages a'lug 26 on thearm 15 in a manner to constantly urge 'rearwardly .member 31 fixedby a rivet 32 and having spaced ngers 33 which are adapted to engage each side of a suitable rib 34 on the 'lli on the ilange17 of the band. Bolts 11, 13 and y I inner side of the band. In order to limit the retractile `movement of the band a stop member 35 of any suitabie form may be provided.

The adjacent ends of the band are provided with ribs 37 and 38 having U-shaped apertures 39 and 40 therein 'tosnu'gly engage the pins 3 and 4 respectively. he pan 10 is provided `with reinforcing plates 45 and 46 in a position beneath the ends of ribs 37 and 38 for rigidly holding the pins 3 and 4 in position when the nuts 7 and 8 are securely tightened onto the outside of plate 46. Plates 45 and 46 are held in position by rivets 51 Apassing through the same and through the forcing plas 45 and 46 for the accommodation ofl pin 3. Cylindrical openings 53 are provided to accommodate the pin 4, as bestv shown in Figure 2.'V The opening-54 is elongated suciently to permit adjustment of the pin 3 to ether with the end of the brake band on whic the rib 38 is formed. y It has been determined from experiments that most of the wear on the brake lining is on the half of the lining between the thrust arm and the flange 38. For this reason it is not necessary to adjust the position of pin 4 as sufiicient of the slack or lost motion resulting from wear on the brake lining may be capensated for by adjustment of the pin 3 o y.

Forl the purpose of eecting the desired adjustment of pin 3 a novel mechanism has been provided comprising a concentric disk 57 (Fig. 4) fitted on an enlarged portion 58 of bolt 3. This concentric disk is of such size that it lies flat on the inner face of the reinforcing plate and is held in position by the slight pressure between the rib 38 and the plate 45 when the shoulder 10' of the-pin 3 is held on plate 45 by the nut 7 as illustrated. The bolt or pin 4 is provided with a similar enlarged portion 61 which is flattened on one side at 62and is adapted to receive a disk 63 (Fig. 5) having an eccentrically positioned opening 64 therein which is flattened at 65 on one side to revent the rotation of the disk 63 relative to t e enlarged portion 61 of the pin 4 when the pin 4 is rotated. The upper ends of pins 3 and 4 are provided with annular channels 66 in which are fitted suitable securing members such as spring collars 67 for pre venting the ribs 37 and 38 of the band from passing off the inner ends of the pins. A slot 68( in the outer end of pin 4 is provided ofv such size to accommodate a screw driver or the like which maybe inserted therein to rotate the pin together with its disk 63 for the purpose of forcing laterally on the disk 57 which abuts it at 70, thereby causing the pins to move laterally relative to each other, the pin 3 being guided in its movement b 'the edgesof the elongated slot 54 throug the reinforcing plates. If the pins are forced farther apart than desired they may be readily adjusted to a position closer to each other by again turning the pin 4 and permitting the coil spring 72 which engages in slots 73 and 74 in ribs 38 and 37 respectively to draw the pins toward each other. The spring 72 also aids in retracting the brake band from engagement with the drums.

l' The modiiication shown in Figure 3 comrises a drum 1 having a. forward brake shoe 5 and a reverse brake shoe 7 6 disposed there- 1n and adapted to have frictional engagement therewith. The brake shoes 75 and 76 are provided with ianges 88 which are proneemt-e vided 1with apertures 7 7 and 7 8 respectively.

engagement with the drum is provided a hydraulic cylinder 7 9 having pistons therein which are connect-edby means of connecting rods and 81 to the upper ends of the brake shoes in a manner such that when :duid pressure is admitted to the cylinder, the upper ends of the brake shoes are actuated into engagement with the drum. Suitable stop members such as pins 82 are providedfor limiting the retractile movement of the brakes upon release of duid pressure.

The brake shoes are retracted from engagement with the drum 'by means of 'coil springs 83 which engage lugs 84 and 85 on the shoes and on the pan respectively. For the purpose of guiding the shoes throughout their range of movement, pins 86 have been provided which pass through elongated slots 87 in the anges 88 of the shoes. The shoes are prevented from passing off the ends of kpins 86 by means of suitable washers 90 and cotter keys 91.

The detailed features of the adjusting mechanism illustrated inthis 'modification are like those heretofore described and more clearly shown in Figure 2. The coil spring 72 in this modification also serves to aid in retracting the shoes from engagement with.

the drums as well as retaining the pins 3 and 4 seated in the bottom of the apertures 77 and 7 8. Since it is an experimental fact that the greater portion of wear on the brake lining is on the lining 92 secured to the forward shoe 75, it is not essential that the pin 4 be adjusted relative to thepan 10 to which it is secured and the elongated slot 54 in which the pin 3 is positioned provides space 'for adequate adjustment under all normal circumstances.

The adjusting mechanism herein described provides 'a relatively inexpensive means by which accurate adjustment may be accomplished and its use is not limited to brakes of the type illustrated in the drawings but may be equally well employed with many other forms of brakes as will be readily apparent to those skilled in the.l art and We do not intend to limit our invention except as set forth in the appended claims. i

We claim as our invention:

1. In a brake mechanism the combination of a drum with a shoe, pivot'means for anchoring the ends of the shoe, a disk on each of said plvots having their ends abutting each other, one offsaid disks beingleccentrically positioned on its pivot and fixed for rotation therewith, whereby the rotation of the last said pivot causes lateral movement of the other said pivot.

2.' In a brake mechanism the vcombination of a drum with a shoe, pivot means for anchoring the ends of the shoe, and abutting members on said pivots, one of which is eccentrically fixed on its pivot vfor rotation therewith, whereby upon rotation of one pivot the other pivot is moved laterally.

3. In a brake mechanism the combination: of a brake drum with cooperating friction means, anchor pins for said friction means, one of said pins having a portion non-'circular in cross section, a disk havngan eccentrically positioned opening therein,.noncircular in shape and fittedsnugly on the non-circular portion of said pin, the periphery of said disk having abutment with the other said pin whereby upon rotation relative lateral movement of said pins is effected.

4. In a brake mechanism the combination of a brake drum with cooperating friction means, anchor pins for said friction means,` one of said pins having a portion non-circular in cross section, a disk having an eccentrically positioned opening of such size and shape to snugly fit .on the non-circular portion of said pin, a concentric disk on the other pin and engaging said eccentric disk, whereby upon rotation of said pin on which the eccentric disk is fixed, relative lateral adjustment of said pins is effected.

5. In a brakemechanism the combination of a brake' drum with cooperating friction means, anchor pins for said friction means,

y one of said pins having a portion non-circular,

in cross section, a disk having'an eccentrically.

positioned opening of such size and shape to snugly fit onthe non-circular portion ofslaid pin, a concentric disk on the other pin-and engaging said eccentric disk, whereby Vupon rotation of said pin onV which they eccentric disk is fixed, relative lateral `adjustment", of said pins is effected, and 'means urging said pins toward each other.

6. In a brake vmechanism the combination element fixed for rotation with the other pin and abutting said concentric element, the pin on whichy said ecentric element is xed being provided with a slot adapted to receive a screw driver and rotate the same and said eccentric element whereby the concentric element with its pin is adjusted laterally, and means on said pin for securing said pin in adjusted positions.

In wit-ness whereof, we hereunto subscribe our names this 11 day of February, 1930. -I-IERBER'I C. BOWEN. JOSEPH R. HEIDLOFF.

of a brake drum with cooperating friction z means, a fixed mounting member for said friction means, anchor pins for-said friction means passing through openings in said mounting member, one of which openings is of such dimension` to permit lateral movement of the pin therein, yielding means urging said pins toward each other, abutting disks on said pins, one of which is eccentrically mounted and fixed for rotation with its pin,l whereby rotation effects relative lateral movement of said pins.

In a brake mechanism the combination of a brake drum with cooperating friction means, a fixed mounting member for said friction means, anchor pins for said friction means passing through openings in said vmounting member, one of which openings is of such dimension to permit lateral movement of the pin therein, yielding means'urging said pins toward each other, a concentric element in one of said pins and eccentric 

